Pike take over Alexander Lake

Species has decimated salmon fishery vital to rural communities

Posted: Tuesday, July 08, 2008

By S.J. KOMARNITSKY

WASILLA - Patches of snow still dotted the grassy edges of Alexander Lake this May when state fisheries biologists Dave Rutz, Sam Ivey and Chris Brockman set about pulling up a hoop net they'd set for pike. As they reeled in the long black net, they gasped. Inside was a mass of 45 pike, and, in that mass were seven "pigs," pike 40-inches or longer with thigh-thick bellies. One measured just shy of four feet and weighed maybe 30 pounds.

"You guys will never see this again," Ivey remembers a stunned Rutz telling him.

He was wrong. A week later, Ivey and his crew did it again.

Alexander Lake and the namesake creek that drains from it into the Susitna River once teemed with salmon and fishermen. Now it boils with a population of pike that, like no other place in Alaska, has decimated the salmon fishery and the lodges that depended on those runs.

Ghost town

As late as the early 1990s, Alexander Creek in the Susitna Valley was a hotspot in Southcentral Alaska for sport fishermen looking for kings and coho salmon.

Anchorage-based air services such as Rust's Flying Service offered daily flights to the mouth while locals and tourists alike motored down the Susitna River in droves from the Deshka Landing.

The king run especially drew a sizeable crowd, with fish showing up in the Alexander before other runs. On a good Memorial Day weekend, the mouth could be clogged with 150 boats and a steady barrage of planes landing on the water to drop off and pick up customers for day trips.

Keith Gabbert, who owns Gabbert's Fish Camp, one of about a half dozen lodges located near the mouth of Alexander Creek, remembers waking up to the buzzing of boats trolling past the family dock. Many were filled with Europeans flown out from Anchorage.

"It'd be 4 a.m. and there'd be 30 Germans and 30 Frenchmen out there already. It'd be a damn armada," he said.

This year, it's like a ghost town.

Gabbert's camp, including its 10 rental cabins, is boarded up, as is another nearby lodge that shut down a few years ago. Closed as well are the four rental cabins that Rust's Flying Service used for its customers.

"It used to be a pretty happening spot," said Willis Thayer, the company's operations manager. But this year "we just didn't see any reason to open."

In February the state Board of Fisheries voted to shut down king salmon fishing on the creek this year because of past dismal returns. The board has also limited coho fishing for the past several years.

Gabbert, who is currently doing odd jobs in Anchorage, has watched the salmon runs and his business dwindle. His parents built the lodge more than 30 years ago. He grew up at the camp and took his first clients fishing before he was in double digits, he said. The fishing back then was good for weeks at a time.

"It's been horrible: What it used to be and what is it now," he said.

Pike heaven

Gabbert thinks both overfishing and pike contributed to the decline of the runs. But biologists say the pike are the reason the king and coho runs won't bounce back. Someone likely introduced pike to Alexander Lake as opposed to the fish migrating into the system, Rutz said.

The voracious predators found a slice of pike heaven.

The area's shallow weedy lakes and numerous slow moving side sloughs provide the perfect habitat for pike while giving salmon fry few places to hide.

Based on studies done in other streams, Rutz said the sloughs along Alexander Creek could each contain hundreds of pike. The population in the lake itself, which is only about three miles long, may top 16,000, he said.

"It is pike heaven. ... I have never in my life heard of a pike population that has been that huge in a lake that size."

Just during the two-week trip this spring to catch and measure pike in the lake, the state crew caught about 1,400, an average of 100 a day, Ivey said.

Voracious predator

The dangers of pike are well documented. Native to parts of Interior and Western Alaska, they are considered an invasive species in Southcentral. They are voracious predators and will feed on anything from frogs to insects to other pike. One well-distributed picture shows a pike with a duckling in its stomach.

In Southcentral Alaska, they are known for having wiped out populations of rainbow trout and Arctic grayling in places like Red Shirt Lake in Willow and Cheney Lake in Anchorage.

But nowhere in the state have they decimated a salmon run like they have at Alexander, said Rutz.

Even in a year where salmon runs have been poor almost everywhere, Alexander Creek stands out, Ivey said. "You know something is wrong when you see one stream, year after year, falling off down the drain," he said.

In 1997, 5,598 kings were counted spawning in the stream. Last year, only 480 were counted. The minimum goal is 2,100. The silver run has also shrunk from reported catches of more than 2,000 fish as recently as eight years ago to 119 in 2006.

The effect of the pike infiltration is visible throughout the system.

Upstream of Alexander Lake, king salmon used to spawn in tributaries that drain into the lake. Now there are none.

Even if a pair of spawners made it through, the resulting fry would have zero chance of surviving the gantlet of pike in the lake and downstream, Rutz said.

The creek's many side sloughs used to boil with so many coho fry picking bugs off the surface it would look like it was raining, he said. Now they are silent.

No good options

So, what to do?

There is little chance of restoring the salmon runs while the pike remain, but getting rid of them is difficult.

There are two ways to eradicate pike, said Kristine Dunker, a state fisheries biologist: drain all the water, or use rotenone, a chemical that suffocates the fish. The latter works in contained systems like small lakes where there are few side channels for pike to hide. The state hopes to apply rotenone this year to kill pike in three lakes including Cheney Lake in Anchorage.

But Alexander Creek and Alexander Lake are a maze of sloughs and side streams. The creek alone winds for more than 40 miles from the lake to the mouth of the Susitna River, Rutz said. Successfully treating all that water is unlikely.

Netting pike is also an option. But it would be expensive and need to be done yearly to keep the population down.

On the positive side, biologists are not that concerned about the pike migrating into and hurting other salmon runs in the Susitna River drainage. Pike are already spread throughout the system and they seem to have reached equilibrium, Rutz said.

Fishermen being what they are, the pike takeover of Alexander Creek and Lake has its up side - a pike fishery.

While nowhere near as popular as the salmon runs, Rust's and Trail Ridge Air now do regular runs to the lake for people looking to fish for pike. Trail Ridge secretary Loree Jensen said the company has a dozen trips scheduled for this summer.